Avoid os.Exit() in function with deferred actions.

main.go

@@ -13,6 +13,10 @@ import (
 )
 
 func main() {
+	os.Exit(main_body())
+}
+
+func main_body() int {
 	var conf_file string
 
 	// Parse args and read config
@@ -27,14 +31,14 @@ func main() {
 	config, err := getConfig(conf_file)
 	if err != nil {
 		fmt.Println("Error reading config file " + conf_file)
-		os.Exit(1)
+		return 1
 	}
 
 	// Open logfile
 	logfile, err := os.OpenFile(config.LogPath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
 	if err != nil {
 		fmt.Println("Error opening log file " + config.LogPath + ".")
-		os.Exit(2)
+		return 2
 	}
 	defer logfile.Close()
 
@@ -67,7 +71,8 @@ func main() {
 			http_server.Shutdown(context.Background())
 			https_server.Shutdown(context.Background())
 		case err := <-errs:
-			log.Fatal(err)
+			log.Println("Fatal: " + err.Error())
 	}
 
+	return 0
 }